A conventional angular positioning structure of a rotary wrench 10 disclosed in TW Publication No. 542053 contains a driving portion 11, the driving portion 11 has an axial hole 111 with inner teeth 112, a grip 12 with an axial seat 121 to be fitted in the axial hole 111 so that the grip 12 allows rotation on the driving portion 11. The axial seat 121 has two grooves 122 defined on two sides thereof and a cavity 123 defined on a middle portion thereof to receive the angular positioning structure. The angular positioning structure contains two retaining blocks 13 axially connected in the two grooves 122 of the axial seat 121 by using two bolts 124, two recesses 131 defined on an inner face of each retaining block 13, an outer toothed section 132 defined on an outer face of one end of the each retaining block 13, and a plane 133 formed on another end of the each retaining block 13. The angular positioning structure also contains a switch 14 axially fixed in the cavity 123 of the axial seat 121, an actuation portion 141 mounted under the switch 14 and extending between the two retaining blocks 13, a resilient element 15 secured in the actuation portion 141, and two positioning tabs 16 abut against two ends of the resilient element 15, such that the resilient element 15 pushes the two positioning tabs 16 to engage with the two recesses 131, thus positioning the two retaining blocks 13. In addition, the cavity 123 of the grip 12 includes a pushing element 12 for abutting against the actuation portion 141 of the switch 14 such that the switch 14 is shifted at different positions. With reference to FIGS. 2 and 3, when a front end of the switch 14 is pressed, the actuation portion 141 drives the two positioning tabs 16 to retain in the two recesses 131 so that two outer toothed sections 132 of the two retaining blocks 13 move inward to disengage from the inner teeth 112 of the driving portion 11, thus shifting the rotary wrench 10 to a quick rotating mode. Referring to FIGS. 4 and 5, a rear end of the switch 12 is pressed so that the actuation portion 141 drives the two positioning tabs 16 to retain in the two recesses 131, hence the two outer toothed section 132 of the two retaining blocks 13 moves outward to engage with the inner teeth 112 of the driving portion 11, thus shifting the rotary wrench 10 to a rotary forcing mode. However, such a conventional rotary wrench 10 has the following defects:
1. As shifting the rotary wrench to the rotary forcing mode, the resilient element 15 pushes the two positioning tabs 16 to retain in the two recesses 131 so that the two outer toothed sections 132 of the two retaining blocks 13 move outward to engage with the inner teeth 112 of the driving portion 11, but the two positioning tabs 16 can not retain in the two recesses 131 securely, so when the user rotates the rotary wrench 10, a reaction force from the inner teeth 112 of the driving portion 11 causes the two retaining blocks 13 to move inward, and then the two outer toothed sections 132 of the two retaining blocks 13 disengage from the inner teeth 112 of the driving portion 11, the driving portion 11 can not be engaged completely.
2. The axial seat 121 has two grooves 122 to receive the two retaining blocks 13, yet the two grooves 122 decrease strength of the axial seat 121, thereby lowering the service life of the axial seat 121.
3. The axial seat 121 has two grooves 122 to axially connect the two retaining blocks 13 therein by using the two bolts 124, and the actuation portion 141 of the switch 14 has the resilient element 15 and the two positioning tabs 16, thus having many connecting parts to increase production cost.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages.